1. Field of the Invention
The present invention relates to a chucking apparatus and method for a cartridge, and more particularly to a chucking apparatus and method for restricting a position of a cartridge accommodating a storage medium and loaded in a recording/reproducing apparatus at a recording/reproducing position thereof.
2. Description of the Related Art
It is important that a cartridge accommodating a storage medium such as an optical disk and a magnetic disk should be loaded always stably in a recording/reproducing apparatus at a predetermined recording/reproducing position, in order to record/reproduce data in/from the storage medium. If a position restriction (chucking) error such as a cartridge float and a cartridge shift occurs at the predetermined recording/reproducing position, it is impossible to correctly record/reproduce data. In order to avoid this, a recording/reproducing apparatus is equipped with a cartridge chucking apparatus for loading/unloading. the cartridge at a predetermined recording/reproducing position. A conventional cartridge chucking apparatus is mounted so that when a cartridge is inserted into the recording/reproducing apparatus, the chucking apparatus holds it, and moves it to a predetermined recording/reproducing position whereat the position in the back/front, right/left and up/down directions is restricted. FIG. 10 is a perspective view of a conventional cartridge chucking apparatus adapted to an MD recording/reproducing apparatus. FIGS. 11A and 11B are diagrams illustrating the operation of the cartridge chucking apparatus shown in FIG. 10 as viewed along an arrow F direction, FIG. 11A shows the state that a cartridge is inserted, and FIG. 11B shows the state that the cartridge is fixed at a predetermined recording/reproducing position.
As shown in FIG. 10, the conventional cartridge chucking apparatus adapted to an MD recording/reproducing apparatus is mounted in a main frame (not shown) of the MD recording/reproducing apparatus and constituted of a loading chassis 80, a base chassis 90 and elastic members 3a and 3b for energizing both the base chassis 90 and loading chassis 80 so as to make them engage with each other. The loading chassis 80 holds a cartridge 1 inserted into an inlet of the MD recording/reproducing apparatus and loads it at, or unloads it from, a predetermined recording/reproducing position. The base chassis 90 restricts (chucks) the position of the cartridge 1 in the front/back, right/left and up/down directions as viewed in FIG. 10, at a loading position to which the loading chassis 80 was moved.
The cartridge 1 accommodates a storage medium (disk) and has two reference holes 2 side by side on the right side as viewed in FIG. 10. These reference holes 2 are formed on the bottom side of the cartridge as concaves with bottoms. The hole 2a is a circle hole, and the hole 2b is an elongated hole with arc sides.
The loading chassis 80 is mounted in a main frame (not shown) of the MD recording/reproducing apparatus as described above and has support shafts 84a and 84b extending from opposite sides. A lift (not shown) for raising/lowering the loading chassis 80 in the main frame is coupled to the support shafts 84a and 84b. As the loading chassis 80 is raised in the main frame, it takes a position corresponding to the inlet (not shown) into which the cartridge 1 is inserted. The loading chassis 80 is provided with spring hooks 86a and 86b projecting from the left side and rear side of the loading chassis 80.
The base chassis 90 is fixed to the bottom of the MD recording/reproducing apparatus and positioned under the loading chassis 80 spaced by a predetermined distance therefrom. The base chassis 90 made of a thin plate has opposite side walls 91a and 91b generally bent at a right angle. The side walls 91a and 91b have guides 94a and 94b formed at generally the center portions thereof, the guides making the support shafts 84a and 84b of the loading chassis 80 be guided and fitted therein. Similar to the loading chassis 80, the base chassis 90 has spring hooks 96 and 96b projecting from the left side and rear side of the base chassis 90. On the surface of the base chassis 90, projected left reference planes 92a and 92d and projected right reference planes 92b and 92c are formed. Of these, the projected right reference planes 92b and 92c have narrow positioning pins 98c and 98b extending upward from the upper surfaces of the planes 92b and 92c. The left reference planes 92a and 92d have the same height as (is flush with) the right reference planes 92b and 92c. 
The spring hooks 86a and 86b of the loading chassis 80 and the spring hooks 96a and 96b of the base chassis 90 are coupled together by the elastic members 3a and 3b and are energized by the elastic members 3a and 3b. Therefore, the elastic members 3a and 3b always energize the loading chassis 80 down to the base chassis 90.
Next, with reference to FIGS. 11A and 11B, the operation of the conventional cartridge chucking apparatus constructed as above will be described. As shown in FIG. 11A, the cartridge 1 is inserted into the inlet of the MD recording/reproducing apparatus and accommodated in the loading chassis 80. At this time, the loading chassis 90 is at the raised position, with their support shafts 84 being held by the lift (not shown). As the cartridge 1 is inserted into the loading chassis 80, this insertion state is detected with a detector (not shown) and the lift is driven to lower the loading chassis 80. The loading chassis 80 is lowered while being maintained horizontally, because the support shafts 84 are held by the lift at the center of the loading chassis 80 which is energized by the elastic members 3a and 3b at opposite ends thereof.
As the loading chassis 80 is lowered horizontally by the lift, as shown in FIG. 11B the positioning pins 98c and 98b of the base chassis 90 are inserted into the reference holes 2, i.e., circle hole 2a and elongated hole 2b of the cartridge 1, by the force of the elastic members 3 so that the position in the front/back, right/left and up/down directions can be restricted.
As described above, with the conventional cartridge chucking apparatus, the positioning pins 98c and 98b are correctly inserted into the reference holes, i.e., circle hole 2a and elongated hole 2b, to fix the cartridge 1, while the loading chassis 80 holding the cartridge 1 is maintained horizontal by the force of the elastic members 3.
With the conventional cartridge chucking apparatus, however, if the cartridge 1 inserted into the loading chassis 80 and temporarily aligned in position shifts in the loading chassis 80 (shift in front/back and right/left directions, rotation and the like) by external shocks such as vibrations, the positioning pins 98c and 98b cannot be inserted into the reference holes 2 even the force of the elastic members 3 is applied.
In order to solve this problem, techniques have been developed which utilize the principle of lever to allow the cartridge 1 to be fitted in with a relatively small force. Such techniques are described, for example, in JP-A-HEI-4-319370.
FIG. 12 is a perspective view of a cartridge chucking apparatus utilizing the principle of lever and adapted to a conventional cartridge recording/reproducing apparatus. FIGS. 13A to 13C are diagrams illustrating the operation of the cartridge chucking apparatus shown in FIG. 12 as viewed along an arrow G direction. FIG. 13A shows the state that a cartridge is inserted, FIG. 13B shows the state that the cartridge is lowered, and FIG. 13C shows the state that the position of the cartridge is restricted and the cartridge is set at a predetermined recording/reproducing position.
As shown in FIG. 12, the conventional cartridge chucking apparatus adapted to a cartridge recording/reproducing apparatus is mounted in a main frame (not shown) of the cartridge recording/reproducing apparatus and constituted of a loading chassis 110, a base chassis 120 and elastic members 3a and 3b for energizing both the base chassis 110 and loading chassis 120 so as to make them engage with each other. The loading chassis 110 holds a cartridge 100 inserted into an inlet of the cartridge recording/reproducing apparatus and loads it at, or unloads it from, a predetermined recording/reproducing position. The base chassis 120 restricts the position of the cartridge 100 in the front/back, right/left and up/down directions as viewed in FIG. 12, at a loading position to which the loading chassis 110 was moved.
The cartridge 100 accommodates a storage medium (disk) and has two reference holes 102 at adjacent front corners as viewed in FIG. 12. These reference holes 102 are formed on the bottom side of the cartridge as concaves with bottoms. The hole 102a is a circle hole, and the hole 102b is an elongated hole with arc sides.
The loading chassis 110 is mounted in a main frame (not shown) of the cartridge recording/reproducing apparatus as described above and has support shafts 114a and 114b extending from opposite sides. A lift (not shown) for raising/lowering the loading chassis 110 in the main frame is coupled to the support shafts 114a and 114b. As the loading chassis 110 is raised in the main frame, it takes a position corresponding to the inlet (not shown) into which the cartridge 100 is inserted. The loading chassis 110 is provided with spring hooks 16a and 16b projecting from the left side and rear side of the loading chassis 110.
The base chassis 120 is fixed to the bottom of the cartridge recording/reproducing apparatus and positioned under the loading chassis 110 spaced by a predetermined distance therefrom. The base chassis 120 made of a thin plate has opposite side walls 121a and 121b generally bent at a right angle. The side walls 121a and 121b have guides 124a and 124b formed generally at the center portions thereof, the guides making the support shafts 114a and 114b of the loading chassis 110 be guided and fitted therein. Similar to the loading chassis 110, the base chassis 120 has spring hooks 126a and 126b projecting from the left side and rear side of the base chassis 120. On the surface of the base chassis 120, projected back reference planes 122a and 122b and projected front reference planes 122b and 122d are formed. Of these, the projected front reference planes 122a and 122c have narrow positioning pins 128a and 128c extending upward from the upper surfaces of the planes 122a and 122c. 
The front reference planes 122a and 122c are slightly higher than the back reference planes 122b and 122d. A height difference between the front reference planes 122a and 122c and the back reference planes 122b and 122d is set to about 0.5 mm. This is because a dimensional tolerance (allowable distortion) of the surface of an ordinary cartridge is in a range of 0.3 mm or smaller, and if this allowable error is covered, the cartridge can be set reliably.
The spring hooks 116a and 116b of the loading chassis 110 and the spring hooks 126a and 126b of the base chassis 120 are coupled together by the elastic members 3a and 3b and are energized by the elastic members 3a and 3b. Therefore, the elastic members 3a and 3b always energize the loading chassis 110 down to the base chassis 120.
Next, with reference to FIGS. 13A to 13C, the operation of the conventional cartridge chucking apparatus constructed as above will be described. As shown in FIG. 13A, the cartridge 100 is inserted into the inlet of the cartridge recording/reproducing apparatus and accommodated in the loading chassis 110. At this time, the loading chassis 90 is at the raised position, with their support shafts 84 being held by the lift. As the cartridge 100 is inserted into the loading chassis 110, this insertion state is detected with a detector (not shown) and the lift is driven to lower the loading chassis 110.
In this case, the loading chassis 110 is lowered while being maintained horizontally, because the support shafts 114a and 114b are held by the lift at the centers of the loading chassis 110 which is energized by the elastic members 3a and 3b at opposite ends thereof, as shown in FIG. 13B.
As the loading chassis 100 is lowered horizontally by the lift, as shown in FIG. 13C the back reference planes 122b and 122d higher than the front reference planes 122a and 122c abut upon the back surface of the cartridge 100, before the positioning pins 128 are inserted into the reference holes 102 or before they are inserted into the reference holes 102 and a load is applied thereto. Therefore, because of the lever principle using the back reference planes 122b and 122d as fulcrum points and the positioning pins 128 as the load points, the cartridge 100 can be set reliably to the predetermined recording/reproducing position, without any suspension of the cartridge 100 at the intermediate points of the positioning pins 128 or inclination of the cartridge 100.
As described above, the conventional cartridge chucking apparatus restricts the position of a cartridge in the front/back, right/left and up/down directions, by effectively utilizing the reference planes for restricting the position in a height direction (up/down direction), the positioning pins for restricting the position in the front/back and right/left directions by inserting them into the cartridge reference holes, and the elastic members for energizing the loading chassis and base chassis in the height direction.
With the conventional cartridge chucking apparatus, the cartridge abuts upon the back side (back reference planes) of the base chassis for temporary position alignment. Therefore, if the cartridge temporarily aligned in position is shifted (shift in front/back and right/left direction, rotation and the like) by external shocks such as vibrations, it becomes difficult for the positioning pins to be inserted into the reference holes, and also the position alignment precision and its reliability of the cartridge change with the operation performance of the lift.
Furthermore, with the conventional cartridge chucking apparatus, two positioning pins are inserted into the two reference holes (circle hole and elongated hole) at the same time by one operation. Therefore, if, for example, the positioning pin is inserted into the circle hole faster than the elongated hole, because of external shocks such as vibrations, the cartridge is fixed and becomes hard to be moved because of the friction of the inserted pin with the hole, and in addition, the position of the circle hole is displaced and the positioning pin becomes difficult to be inserted.
Still further, with the conventional cartridge chucking apparatus, the cartridge is supported at four positions including two front reference planes and two back planes, or two right reference planes and two left reference planes. Therefore, the abut surface of a cartridge is required to have high flatness. If the abut surface is uneven, the height reference may be made slanted when the position is restricted so that the cartridge is set with some play or a spindle motor and the like for rotating a disk is required to have a high rotation precision and a high deviation precision.
It is an object of the present invention to solve the above-described problems and provide a chucking apparatus capable of correctly and stably restricting the position of a cartridge and improving a reliability and precision of position alignment.
In order to solve the above-described problems, the present invention provides a chucking apparatus for loading/unloading a cartridge accommodating a storage medium into/from a recording/reproducing apparatus, the cartridge having a circle hole and an elongate hole as reference holes in front and rear along an insertion direction of the cartridge, the reference holes restricting a position in horizontal direction of the cartridge, the chucking apparatus comprising: a loading chassis disposed in the recording/reproducing apparatus, the loading chassis including projections in contact with upper surface of the cartridge for holding the cartridge and for restricting a position in height direction of the cartridge and support members projecting from opposite sides of the loading chassis and supported by a lifting mechanism; a base chassis disposed in the recording/reproducing apparatus, the base chassis including reference planes in contact with bottom surfaces of the cartridge including the reference holes at a predetermined recording/reproducing position to which the loading chassis is moved, to squeeze the cartridge with the projections and restrict the position in height direction of the cartridge, and positioning pins projecting from surfaces of the reference planes for entering the reference holes and having in contact with the bottom surfaces of the reference holes to restrict the position in horizontal direction of the cartridge; and a loading mechanism adapted to insert the positioning pin into the circle hole and thereafter insert the other positioning pin into the elongated hole.
Preferably, the chucking apparatus further comprises elastic members engaged between the loading chassis and the base chassis, wherein the loading mechanism is arranged so that the positioning pin is first inserted into the circle hole and thereafter the other positioning pin is inserted into the elongated hole owing to the balance of the elastic member in front and rear of the support member as a fulcrum.
It is preferable to use a coil spring as the elastic member.
Further, as a preferable embodiment, the loading chassis includes a plurality of support members disposed in front and rear along the insertion direction and the loading mechanism has a slider having a guide groove for determining the position in height direction of the support member when loading engaged with the support member.
And, the guide groove of the slider consists of a slope groove part and upper and lower horizontal groove parts sandwiching the slope groove part, and the guide groove is arranged so that the support member at the circle hole side of the loading chassis moves to the slope groove part of the guide groove prior to the movement of the support member at the elongated hole side when the cartridge moves from the insertion position to the reproduction position.
And also, the guide groove consists of a slope groove part and upper and lower horizontal glove parts sandwiching the slope groove part, and an angle of the slope groove part of the guide groove with respect to a horizontal plane is set us so that an angle of the slope at the circle hole side is larger than an angle of the slope at the elongated hole.
The present invention provides a chucking method for loading a cartridge accommodating a storage medium into a recording/reproducing apparatus, the cartridge having a circle hole an elongate hole as reference holes in front and rear along an insertion direction of the cartridge, the reference holes restricting a position in horizontal direction of the cartridge, the chucking method comprising the steps of: inserting the cartridge into a loading chassis positioned in a horizontal plane; causing the loading chassis holding the cartridge to move to a position for recording/reproducing so obliquely that the circle hole side of the cartridge becomes lower than the longate hole thereof; and positioning horizontally the loading chassis holding the cartridge in the position for recording/reproducing.